I don't think Leo was great in it. He was good, but I wasn't buying into the prosthetics or his character's arc, much as I found the latter segments of The Reader far less convincing than Winslet's genius work in the beginning. That said, I wouldn't generalize an opinion on Leo from this performance alone, or his other indifferent ones (which includes Gangs of New York). I find it hard to believe that someone could watch The Basketball Diaries, Blood Diamond, Revolutionary Road, Catch Me If You Can, and The Departed and then claim that Leo is the same in everything. He may not have Gary Oldman's freakish technical range (Drexl Spivey, Sid Vicious, and George Smiley is just
and outclasses every actor in the game, not just Leo), but these characters - once you start watching the films - have nothing in common, and are absolutely persuasive. Some actors like the superb Russell Crowe are very capable of creating performances out of meagre textual scaffolding (I call those actors "overreaders"), while others like DiCaprio are a little more handicapped to function best with a solid character on the page through which to project his unparalleled emotional intensity, as in Revolutionary Road.
Oh, and Eastwood is a massively overrated director (I don't even like Unforgiven much, and thought it had stalled a bit around the time Eastwood was getting beaten in the saloon), and I think Dustin Lance Black's work on Milk and J. Edgar mediocre.